Disadvantage Of Rigid Pavement

Pavements constitute the most widely used part of the nation’s infrastructure for transportation of people and goods. The quality of roads determine the economy of a country and hence the quality of our lives. In India, road transport holds more than 60% of the freight and more than 80% of the passenger traffic. Roads are essential for the transport of goods and passengers. Village roads are crucial for the basic minimum connectivity for the upliftment of the social and economic condition of the rural people. Such roads give access to employment, ways to transport agricultural produce and access to health care and social services.
Pavement is the actual travel surface, made durable and serviceable to withstand the traffic load commuting upon

Rigid pavement, because of PCC’s high elastic modulus, tends to distribute the load over a wider area of subgrade . The concrete slab itself takes most of the load and it plays a vital role in rigid pavement’s structural capacity. Flexible pavement uses more number of layers and distributes loads over a relatively small area. It depends on a combination of layers for transmitting the load to subgrade. Flexible pavements require maintenance or rehabilitation every 10 to 15 years. While the Rigid pavements, can serve 20 to 40 years with little or no maintenance or rehabilitation. So, it is of no surprise that rigid pavements are often used in urban, high traffic areas.
STRESSES IN RIGID PAVEMENT
• Frictional stresses: These are stresses that are caused due to the contraction and expansion of slabs because of increase or decrease in temperature. As the slab is in contact with the subgrade the expansion and contraction movements of the slab will be restrained by the friction between the bottom layer of the slab and the soil

The research methodology initiated with an extensive literature survey on the effects of nonlinear temperature distribution on thermal stresses in concrete pavement. From the literatures, the basic methodology of the analysis of the temperature and the experimental study was the same except for the introduction of different support conditions.
The materials like manufactured sand, crushed stone aggregate, Ordinary Portland cement were collected from the local sources and preliminary tests were conducted to determine their physical properties. Experimental tests on fresh and hardened concrete were conducted. To carry out the study, mainly two support conditions were given for the slab – one where the slab is fully supported by the natural subgrade and the other where the slab is supported only at its four corners. The following approach was adopted to meet the objectives of the respective